The Sundance Film Festival is in full swing in Park City, UT, and celebrities are bringing their cold-weather style A-game. With temperatures dipping into the freezing zone, warm layers and protective outerwear are key. Shailene Woodley caught our eye in Marni, while Jessica Biel and Naomi Watts went for outfits made up of wintry basics. Watch our Sundance style recap for all the details! On Allison McNamara: Forever 21 top.